Widespread multitissue deletions of the mitochondrial genome in the Pearson marrow-pancreas syndrome

Pearson’s Marrow-Pancreas Syndrome in 2 Turkish Children

“…Family studies in our patients have no clue about inheritance of the disease, al though in the presence of a consanguineous marriage in case 2, a recessively inherited abnormality causing mtDNA deletion could not be ruled out. Recent studies showed that mtDNA deletion was present in several or gans, indicating that Pearson's syndrome is a multisystem disorder [3,4].…”

Deletion in Blood Mitochondrial DNA in Kearns-Sayre Syndrome

“…Previous investigators had shown that the same mtDNA deletion can occur in both of these syndromes (3,9). The differential phenotypic expression has generally been ascribed to the different tissue distribution of the deleted mtDNA molecules, in particular the presence of a large proportion of such molecules in the blood of patients with Pearson's syndrome and a tiny proportion in those with KSS (2,(4)(5)(6)(7)(8)(9)(10). However, in our patient, 75% of the mtDNA molecules in the peripheral blood have a large deletion without any corresponding phenotype.…”

“…9). The abnormal mtDNA molecules can be detected in most tissues and, in contrast to KSS, are always predominant in the peripheral blood (8)(9)(10).…”

Molecular bases of inherited bone marrow failures : Shwachman-Diamond syndrome and Diamond Blackfan anemia.

“…It is often fatal in infancy. Patients that survive past early neonatal life develop symptoms similar to Kearns-Sayre Syndrome, which is a mitochondrial myoencephalopathy (a disorder of muscle and brain tissues) (McShane et al, 1991;Rotig et al, 1990;van den Ouweland et al, 2000). Patient samples were found to have large deletions and/or rearrangements in mitochondrial DNA which disrupt energy metabolism.…”

“…Patient samples were found to have large deletions and/or rearrangements in mitochondrial DNA which disrupt energy metabolism. This preferentially affects tissues requiring a high threshold of mitochondrial function like the central nervous system and skeletal muscle (Baerlocher et al, 1992;Blaw and Mize, 1990;Cormier et al, 1990;Kleinle et al, 1997;Lee et al, 2007;Niaudet et al, 1994;Santorelli et al, 1996;van den Ouweland et al, 2000). Sideroblasts are also evident in X-linked sideroblastic anemia caused by defects in the gene encoding δ-amino levulinic acid synthase.…”